From 40bc5985f4b8149eea9ad8ad094fdde81498e017 Mon Sep 17 00:00:00 2001
From: Christopher Neugebauer <chrisjrn@gmail.com>
Date: Wed, 6 Apr 2016 15:40:16 +1000
Subject: [PATCH] Propagates the error messages up from enabling condition
 testing

---
 registrasion/controllers/cart.py       |  9 ++-----
 registrasion/controllers/conditions.py | 37 +++++++++++++++++++++++++-
 registrasion/views.py                  |  2 ++
 3 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/registrasion/controllers/cart.py b/registrasion/controllers/cart.py
index e8310f4b..def22c17 100644
--- a/registrasion/controllers/cart.py
+++ b/registrasion/controllers/cart.py
@@ -120,14 +120,12 @@ class CartController(object):
         # Test each product limit here
         for product, quantity in product_quantities:
             if quantity < 0:
-                # TODO: batch errors
                 errors.append((product, "Value must be zero or greater."))
 
             prod = ProductController(product)
             limit = prod.user_quantity_remaining(self.cart.user)
 
             if quantity > limit:
-                # TODO: batch errors
                 errors.append((
                     product,
                     "You may only have %d of product: %s" % (
@@ -149,7 +147,6 @@ class CartController(object):
             to_add = sum(i[1] for i in by_cat[category])
 
             if to_add > limit:
-                # TODO: batch errors
                 errors.append((
                     category,
                     "You may only have %d items in category: %s" % (
@@ -164,10 +161,8 @@ class CartController(object):
         )
 
         if errs:
-            # TODO: batch errors
-            errors.append(
-                ("enabling_conditions", "An enabling condition failed")
-            )
+            for error in errs:
+                errors.append(error)
 
         if errors:
             raise CartValidationError(errors)
diff --git a/registrasion/controllers/conditions.py b/registrasion/controllers/conditions.py
index 9a0b26df..55b1a7d5 100644
--- a/registrasion/controllers/conditions.py
+++ b/registrasion/controllers/conditions.py
@@ -44,6 +44,26 @@ class ConditionController(object):
         except KeyError:
             return ConditionController()
 
+
+    SINGLE = True
+    PLURAL = False
+    NONE = True
+    SOME = False
+    MESSAGE = {
+        NONE: {
+            SINGLE:
+                "%(items)s is no longer available to you",
+            PLURAL:
+                "%(items)s are no longer available to you",
+        },
+        SOME: {
+            SINGLE:
+                "Only %(remainder)d of the following item remains: %(items)s",
+            PLURAL:
+                "Only %(remainder)d of the following items remain: %(items)s"
+        },
+    }
+
     @classmethod
     def test_enabling_conditions(
             cls, user, products=None, product_quantities=None):
@@ -83,6 +103,8 @@ class ConditionController(object):
         # if there are no mandatory conditions
         non_mandatory = defaultdict(lambda: False)
 
+        messages = {}
+
         for condition in all_conditions:
             cond = cls.for_condition(condition)
             remainder = cond.user_quantity_remaining(user)
@@ -104,12 +126,21 @@ class ConditionController(object):
                 consumed = 1
             met = consumed <= remainder
 
+            if not met:
+                items = ", ".join(str(product) for product in all_products)
+                base = cls.MESSAGE[remainder == 0][len(all_products) == 1]
+                message = base % {"items": items, "remainder": remainder}
+
             for product in all_products:
                 if condition.mandatory:
                     mandatory[product] &= met
                 else:
                     non_mandatory[product] |= met
 
+                if not met and product not in messages:
+                    messages[product] = message
+
+
         valid = defaultdict(lambda: True)
         for product in itertools.chain(mandatory, non_mandatory):
             if product in mandatory:
@@ -119,7 +150,11 @@ class ConditionController(object):
                 # Otherwise, we need just one non-mandatory condition met
                 valid[product] = non_mandatory[product]
 
-        error_fields = [product for product in valid if not valid[product]]
+        error_fields = [
+            (product, messages[product])
+            for product in valid if not valid[product]
+        ]
+
         return error_fields
 
     def user_quantity_remaining(self, user):
diff --git a/registrasion/views.py b/registrasion/views.py
index 3f9dbf4f..1cb4ec57 100644
--- a/registrasion/views.py
+++ b/registrasion/views.py
@@ -337,6 +337,8 @@ def set_quantities_from_products_form(products_form, current_cart):
             product, message = ve_field.message
             if product in field_names:
                 field = field_names[product]
+            elif isinstance(product, rego.Product):
+                continue
             else:
                 field = None
             products_form.add_error(field, message)